A typical digital video broadcast is transmitted as a series of frames, with each frame composed of a plurality of lines and each line composed of a plurality of pixels. The color of a pixel can be represented as a mathematical combination of a set of colors which, in some systems, is treated like a dot position in a three-dimensional color space. One conventional color model is called YUV color space, in which the color representation is divided into two types of data, namely, luminance (i.e., overall brightness or “luma”) data (“Y”) and chrominance (i.e., color or “chroma”) data (“U” and “V”). In a YUV system, the chrominance data (U, V) is transmitted in such a way that it can be disregarded by a black and white receiver, which uses only the luminance data (Y) to display a black and white picture, while a color receiver decodes both the luminance and the chrominance data to display a color picture. Another typical, similar color model is YCbCr color space, in which luminance is represented by Y data and chrominance is represented by Cb and Cr data.
Some digital video signal processing integrated circuits have two main data paths, one for chroma signals and one for luma signals. Most of the functions of such integrated circuits may treat these two paths as independent. However, some processing operations may require chroma and luma data to be synchronized at the first pixel of each video line. But historical approaches for synchronizing luma and chroma data have required undesirably high numbers of logic gates and/or memory devices which have increased the sizes and costs of video processing circuits and/or slowed processing speeds.
The present invention is directed to overcoming some of the drawbacks of conventional approaches for synchronizing luma and chroma data.